San Francisco's plan to offer sex change benefits to city employees appears headed for ap proval after winning a key endorsement yesterday from a Board of Supervisors committee. If the full board approves the proposal Monday as expected, San Francisco would become the only government employer in the nation to include such benefits in its health plan.

Supporters hope the move will ignite a domino-like effect in which other cities, states and businesses provide health insurance coverage to workers seeking to change genders.

"I really invite you to take part in history right now . . . because as goes San Francisco goes the rest of the nation," Marcus Arana, a transsexual city employee working for the Human Rights Commission, told the board's Finance Committee yesterday during a public hearing on the proposal.

City officials said they'd heard from a major HMO, a couple of nonprofit organizations and workers from the University of California at San Francisco who wanted more information on the city's proposed effort to see about instituting similar coverage.

No one testified against the proposal for city workers at yesterday's hearing, but the plan remains controversial.

Since the plan first received widespread media attention in February, supervisors have been inundated with e-mails and phone calls, mainly from people who are against the idea. But no official opposition has emerged, either from community groups or associations representing active or retired city workers.

The new benefits would kick in July 1, with restrictions. Only those workers who have been enrolled in the city's health plan for at least a year would be eligible, and they must have a medical diagnosis from a doctor. The condition is known as gender dysphoria, in short, a condition in which a person is determined to feel discomfort with the gender into which he or she is born.

"I was 5 or 6 when I realized that there was something between my legs that was useless to me except (to urinate)," said Claire Skiffington, a 55-year-old administrator with the city's Department of Public Health. She began her transition from male to female seven years ago with hormones and psychotherapy.

Sex change treatments may include hormone therapy, psychotherapy and surgery. While hormone therapy and counseling are relatively inexpensive, surgery is costly. For males changing to females, surgery costs about $37,000. The surgical costs for females becoming males runs considerably more, about $77,000. The surgeries are for genital reconstruction and mastectomies. Purely cosmetic changes, such as breast augmentation, would not be covered.

Under the proposal, there would be a lifetime cap of $50,000 per person for the procedures. The benefit also won't cover the entire cost of surgery. The employee's co-payment ranges from 15 to 50 percent.

An actuary for the city's Health Service System said the new benefits might cost $1.75 million for the first year, based on calculations that 35 people would take advantage of the benefits. However, city officials say the number most likely would be considerably less, perhaps no more than three or four. There are about a dozen known transsexuals working for the city.

To pay for the new benefits, all employees in the Health Service System, which includes 37,000 people working for the city, the public schools and the community college district, would be charged about $1.70 a month. The 17,000 or so retired employees would also pay. Backers of the plan hope that the cost will come down in future years, once there's a better idea of how many people will take advantage of the program.

The proposed benefits package includes coverage for several other new initiatives, among them infertility treatment, hearing aids, Viagra and acupuncture.

Supervisor Mark Leno, who has backed the sex change benefits, said they'd be a natural extension of city laws that ban discrimination against transgender people and require equal benefits for domestic partners.

"By moving this legislation forward, we'll be making an equal statement, that we should recognize the fact of our transgender population in San Francisco, we should afford our transgender brothers and sisters equal dignity,

respect and honor to be able to participate as full citizens in San Francisco. "

Skiffington, the Health Department administrator, said all the attention drawn to the new coverage had had an unintended benefit: "It has made it easier for my family to discuss it." Now, she said, the issue isn't stuffed into the closet.

"As it (transsexualism) becomes more known," she said, "it will become more accepted."